A wide variety of disposable absorbent articles are designed not only to be efficient in the absorption of body fluids such as urine, blood, menses and the like, but also to be sanitary and comfortable in-use, are known in literature. Disposable absorbent products of this type generally comprise a fluid-permeable topsheet material, an absorbent core (or a fluid storage layer), and a fluid-impermeable backsheet material. Various shapes, sizes and thicknesses of such articles have been explored in an attempt to make their use more comfortable and convenient.
Recently, research has been focused on the removal of unpleasant odors. Many body fluids have an unpleasant odor (or an malodor), or develop such an odor when in contact with air and/or bacteria for prolonged periods. Urine and/or other exudates absorbed into the absorbent article are converted to ammonia by urease produced by skin-flora, i.e., a group of normal microorganisms on the skin. This ammonia could become a source of unpleasant odors.
Many attempts have been made to suppress the development of unpleasant odors. One approach is to apply antimicrobial materials into the absorbent article. Antimicrobial materials and bactericides in general are chemical compositions that are used to prevent microbiological contamination and deterioration of products, materials, and systems. Such antimicrobial materials and bactericides effectively work for removal or reduction of unpleasant odors developed from disposable absorbent articles which have already absorbed body fluids. Another approach is to apply an odor absorbing material into the absorbent article. The odor absorbing material absorbs unpleasant odors when the unpleasant odors develop while it may not prevent microbiological contamination and deterioration of products. Further, a perfume may be used to mask the unpleasant odors when the unpleasant odors develop.
Each of these approaches is effective in suppressing the development of unpleasant odors or in masking the unpleasant odors even when the unpleasant odors develop. Each of these approaches, however, has each unique drawback. While a hydrogel forming material comprising polyacrylic acid is known to absorb unpleasant odors derived from urine and/or other body exudates, the hydrogel forming material does not provide benefits noticeably perceivable to consumers with respect to odor control. Therefore, an antimicrobial material or a perfume has been added to the absorbent article to further enhance the odor control of the absorbent article. However, just adding the antimicrobial material into the absorbent article may cause skin safety issues or dysfunction of the antimicrobial material if the disposition of the antimicrobial material is not appropriate. Further, the perfume may cause the user to perceive too strong smell of perfume or may rapidly vaporize to lose the masking effect of the unpleasant odor if the disposition of the perfume is not appropriate. None of prior art has identified an disposable absorbent article to effectively dispose the odor control system comprising an antimicrobial material, an odor masking material and an odor absorbing and/or adsorbing material in the disposable absorbent article.
Based on the foregoing, there is a need for a disposable absorbent article which has an effective disposition of the odor control system so that each of the odor control ingredients effectively works in the disposable absorbent article.